[Mesa-dev] [PATCH 06/22] mesa: Add decoding functions for GL_COMPRESSED_RGBA8_ETC2_EAC
Anuj Phogat
anuj.phogat at gmail.com
Fri Nov 9 23:29:53 PST 2012
Signed-off-by: Anuj Phogat <anuj.phogat at gmail.com>
---
src/mesa/main/texcompress_etc.c | 146 +++++++++++++++++++++++++++++++++++++-
src/mesa/main/texcompress_etc.h | 7 ++
2 files changed, 149 insertions(+), 4 deletions(-)
diff --git a/src/mesa/main/texcompress_etc.c b/src/mesa/main/texcompress_etc.c
index eacfb0d..c04ba8d 100644
--- a/src/mesa/main/texcompress_etc.c
+++ b/src/mesa/main/texcompress_etc.c
@@ -26,6 +26,8 @@
* GL_OES_compressed_ETC1_RGB8_texture support.
* Supported ETC2 texture formats are:
* GL_COMPRESSED_RGB8_ETC2
+ * GL_COMPRESSED_SRGB8_ETC2
+ * GL_COMPRESSED_RGBA8_ETC2_EAC
*/
#include <stdbool.h>
@@ -39,7 +41,7 @@
struct etc2_block {
int flipped;
int distance;
- uint32_t pixel_indices;
+ uint64_t pixel_indices[2];
const int *modifier_tables[2];
GLboolean is_ind_mode;
GLboolean is_diff_mode;
@@ -48,11 +50,33 @@ struct etc2_block {
GLboolean is_planar_mode;
GLubyte base_colors[3][3];
GLubyte paint_colors[4][3];
+ GLubyte base_codeword;
+ GLubyte multiplier;
+ GLubyte table_index;
};
static const int etc2_distance_table[8] = {
3, 6, 11, 16, 23, 32, 41, 64 };
+static const int etc2_modifier_tables[16][8] = {
+ { -3, -6, -9, -15, 2, 5, 8, 14},
+ { -3, -7, -10, -13, 2, 6, 9, 12},
+ { -2, -5, -8, -13, 1, 4, 7, 12},
+ { -2, -4, -6, -13, 1, 3, 5, 12},
+ { -3, -6, -8, -12, 2, 5, 7, 11},
+ { -3, -7, -9, -11, 2, 6, 8, 10},
+ { -4, -7, -8, -11, 3, 6, 7, 10},
+ { -3, -5, -8, -11, 2, 4, 7, 10},
+ { -2, -6, -8, -10, 1, 5, 7, 9},
+ { -2, -5, -8, -10, 1, 4, 7, 9},
+ { -2, -4, -8, -10, 1, 3, 7, 9},
+ { -2, -5, -7, -10, 1, 4, 6, 9},
+ { -3, -4, -7, -10, 2, 3, 6, 9},
+ { -1, -2, -3, -10, 0, 1, 2, 9},
+ { -4, -6, -8, -9, 3, 5, 7, 8},
+ { -3, -5, -7, -9, 2, 4, 6, 8},
+};
+
/* define etc1_parse_block and etc. */
#define UINT8_TYPE GLubyte
#define TAG(x) x
@@ -400,7 +424,7 @@ etc2_rgb8_parse_block(struct etc2_block *block, const GLubyte *src)
block->flipped = (src[3] & 0x1);
}
- block->pixel_indices =
+ block->pixel_indices[0] =
(src[4] << 24) | (src[5] << 16) | (src[6] << 8) | src[7];
}
@@ -413,8 +437,8 @@ etc2_rgb8_fetch_texel(const struct etc2_block *block,
/* get pixel index */
bit = y + x * 4;
- idx = ((block->pixel_indices >> (15 + bit)) & 0x2) |
- ((block->pixel_indices >> (bit)) & 0x1);
+ idx = ((block->pixel_indices[0] >> (15 + bit)) & 0x2) |
+ ((block->pixel_indices[0] >> (bit)) & 0x1);
if (block->is_ind_mode || block->is_diff_mode) {
/* Use pixel index and subblock to get the modifier */
@@ -456,6 +480,51 @@ etc2_rgb8_fetch_texel(const struct etc2_block *block,
}
}
+static void
+etc2_alpha8_fetch_texel(const struct etc2_block *block,
+ int x, int y, GLubyte *dst)
+{
+ int modifier, alpha, bit, idx;
+ /* get pixel index */
+ bit = ((3 - y) + (3 - x) * 4) * 3;
+ idx = (block->pixel_indices[1] >> bit) & 0x7;
+ modifier = etc2_modifier_tables[block->table_index][idx];
+ alpha = block->base_codeword + modifier * block->multiplier;
+ dst[3] = etc2_clamp(alpha);
+}
+
+static void
+etc2_alpha8_parse_block(struct etc2_block *block, const GLubyte *src)
+{
+ block->base_codeword = src[0];
+ block->multiplier = (src[1] >> 4) & 0xf;
+ block->table_index = src[1] & 0xf;
+ block->pixel_indices[1] = (((uint64_t)src[2] << 40) |
+ ((uint64_t)src[3] << 32) |
+ ((uint64_t)src[4] << 24) |
+ ((uint64_t)src[5] << 16) |
+ ((uint64_t)src[6] << 8) |
+ ((uint64_t)src[7]));
+}
+
+static void
+etc2_rgba8_parse_block(struct etc2_block *block, const GLubyte *src)
+{
+ /* RGB component is parsed the same way as for MESA_FORMAT_ETC2_RGB8 */
+ etc2_rgb8_parse_block(block, src + 8);
+
+ /* Parse Alpha component */
+ etc2_alpha8_parse_block(block, src);
+}
+
+static void
+etc2_rgba8_fetch_texel(const struct etc2_block *block,
+ int x, int y, GLubyte *dst)
+{
+ etc2_rgb8_fetch_texel(block, x, y, dst);
+ etc2_alpha8_fetch_texel(block, x, y, dst);
+}
+
/**
* Convert an 8-bit sRGB value from non-linear space to a
* linear RGB value in [0, 1].
@@ -557,6 +626,42 @@ etc2_unpack_srgb8(uint8_t *dst_row,
}
}
+static void
+etc2_unpack_rgba8(uint8_t *dst_row,
+ unsigned dst_stride,
+ const uint8_t *src_row,
+ unsigned src_stride,
+ unsigned width,
+ unsigned height)
+{
+ /* If internalformat is COMPRESSED_RGBA8_ETC2_EAC, each 4 × 4 block of
+ RGBA8888 information is compressed to 128 bits. To decode a block, the
+ two 64-bit integers int64bitAlpha and int64bitColor are calculated.
+ */
+ const unsigned bw = 4, bh = 4, bs = 16, comps = 4;
+ struct etc2_block block;
+ unsigned x, y, i, j;
+
+ for (y = 0; y < height; y += bh) {
+ const uint8_t *src = src_row;
+
+ for (x = 0; x < width; x+= bw) {
+ etc2_rgba8_parse_block(&block, src);
+
+ for (j = 0; j < bh; j++) {
+ uint8_t *dst = dst_row + (y + j) * dst_stride + x * comps;
+ for (i = 0; i < bw; i++) {
+ etc2_rgba8_fetch_texel(&block, i, j, dst);
+ dst += comps;
+ }
+ }
+ src += bs;
+ }
+
+ src_row += src_stride;
+ }
+}
+
/* ETC2 texture formats are valid in glCompressedTexImage2D and
* glCompressedTexSubImage2D functions */
GLboolean
@@ -575,6 +680,14 @@ _mesa_texstore_etc2_srgb8(TEXSTORE_PARAMS)
return GL_FALSE;
}
+GLboolean
+_mesa_texstore_etc2_rgba8_eac(TEXSTORE_PARAMS)
+{
+ ASSERT(0);
+
+ return GL_FALSE;
+}
+
void
_mesa_fetch_texel_2d_f_etc2_rgb8(const struct swrast_texture_image *texImage,
GLint i, GLint j, GLint k, GLfloat *texel)
@@ -615,10 +728,31 @@ _mesa_fetch_texel_2d_f_etc2_srgb8(const struct swrast_texture_image *texImage,
texel[ACOMP] = 1.0f;
}
+void
+_mesa_fetch_texel_2d_f_etc2_rgba8_eac(const struct swrast_texture_image *texImage,
+ GLint i, GLint j, GLint k, GLfloat *texel)
+{
+ struct etc2_block block;
+ GLubyte dst[4];
+ const GLubyte *src;
+
+ src = (const GLubyte *) texImage->Map +
+ (((texImage->RowStride + 3) / 4) * (j / 4) + (i / 4)) * 16;
+
+ etc2_rgba8_parse_block(&block, src);
+ etc2_rgba8_fetch_texel(&block, i % 4, j % 4, dst);
+
+ texel[RCOMP] = UBYTE_TO_FLOAT(dst[0]);
+ texel[GCOMP] = UBYTE_TO_FLOAT(dst[1]);
+ texel[BCOMP] = UBYTE_TO_FLOAT(dst[2]);
+ texel[ACOMP] = UBYTE_TO_FLOAT(dst[3]);
+}
+
/**
* Decode texture data in any one of following formats:
* `MESA_FORMAT_ETC2_RGB8`
* `MESA_FORMAT_ETC2_SRGB8`
+ * `MESA_FORMAT_ETC2_RGBA8_EAC`
*
* The size of the source data must be a multiple of the ETC2 block size
* even if the texture image's dimensions are not aligned to 4.
@@ -645,4 +779,8 @@ _mesa_unpack_etc2_format(uint8_t *dst_row,
etc2_unpack_srgb8(dst_row, dst_stride,
src_row, src_stride,
src_width, src_height);
+ else if (format == MESA_FORMAT_ETC2_RGBA8_EAC)
+ etc2_unpack_rgba8(dst_row, dst_stride,
+ src_row, src_stride,
+ src_width, src_height);
}
diff --git a/src/mesa/main/texcompress_etc.h b/src/mesa/main/texcompress_etc.h
index 1dc1d5a..2191c97 100644
--- a/src/mesa/main/texcompress_etc.h
+++ b/src/mesa/main/texcompress_etc.h
@@ -40,6 +40,9 @@ _mesa_texstore_etc2_rgb8(TEXSTORE_PARAMS);
GLboolean
_mesa_texstore_etc2_srgb8(TEXSTORE_PARAMS);
+GLboolean
+_mesa_texstore_etc2_rgba8_eac(TEXSTORE_PARAMS);
+
void
_mesa_fetch_texel_2d_f_etc1_rgb8(const struct swrast_texture_image *texImage,
GLint i, GLint j, GLint k, GLfloat *texel);
@@ -49,6 +52,9 @@ _mesa_fetch_texel_2d_f_etc2_rgb8(const struct swrast_texture_image *texImage,
void
_mesa_fetch_texel_2d_f_etc2_srgb8(const struct swrast_texture_image *texImage,
GLint i, GLint j, GLint k, GLfloat *texel);
+void
+_mesa_fetch_texel_2d_f_etc2_rgba8_eac(const struct swrast_texture_image *texImage,
+ GLint i, GLint j, GLint k, GLfloat *texel);
void
_mesa_etc1_unpack_rgba8888(uint8_t *dst_row,
@@ -65,4 +71,5 @@ _mesa_unpack_etc2_format(uint8_t *dst_row,
unsigned src_width,
unsigned src_height,
gl_format format);
+
#endif
--
1.7.7.6
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